wmaxt
Staff Sergeant
How do I post a graph from my computer to the forum?
F4U F6F P-38 P-47 or P-51 Which plane was best by war's end
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the lancaster kicks ass
Major General
- 19,937
- Dec 20, 2003
what's it saved as??
A
Anonymous
Guest
wmaxt said:
You have two options.
1) attach the graphic to the post, it will then be uploaded (when you hit "add attachment") and appear at the end of the post. Allowable types and sizes found here -> http://www.ww2aircraft.net/forum/attach_rules.php
2) upload the graphic to the web (or locate one already on the web), either your own webspace or to another post on this forum (I have a thread in the sigs forum for this purpose) and then put the url pointing to it in your post and surround with the image tags. Example:
{img}http://www.wherever.net/yourimage.jpg{/img}
where square brackets are used instead of curly brackets. This allows you to put the image in the middle of the post instead of at the end.
Note: to get the url of an image, right click on the image, select "properties", highlight the url to the image, and then copy (ctrl+c) the url address into the copy buffer. Then switch to your post input and paste (ctrl+v) it into the post. Then put the image tags around it.
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Lunatic
wmaxt
Staff Sergeant
Thanks! I copied it off so I can keep it. I was going to post the graphs from the Planes and pilots of WWII of the Lockheed P-38 tests but found out after a little checking they are Copyrighted and are forbidden to post on a public forum with out specific permission.
These graphs are in the third part of the P-38 article and comfirm the P-38 performance figures I have been submitting. The tests were done using fresh aircraft in combat average trim - half internal fuel, ammo ballast, guns and no external stores. They also show 1,725hp @ 64in/hg, 28,700ft (Allison sometimes states 1,750hp for the 111/113 engines) 5.0min +/- to 20,000ft, and 443+/- top speeds. It also shows the "Standard" performace figures of 1,425hp @54in/hg (military power) and 414mph and a Normal power 1,100hp climb of 9+ min to 20,000ft. P-51 info is also included for comparison. I have seen this info elsewhere and will post it when I find it again in a format I can post.
The source of this information is in part Warren Bodie who is considered in aviation and aviation history circles a serious, respected, accurate and reliable source.
The Planes and pilots web page is at http://home.att.net/~C.C.Jordan/index.html
wmaxt
These graphs are in the third part of the P-38 article and comfirm the P-38 performance figures I have been submitting. The tests were done using fresh aircraft in combat average trim - half internal fuel, ammo ballast, guns and no external stores. They also show 1,725hp @ 64in/hg, 28,700ft (Allison sometimes states 1,750hp for the 111/113 engines) 5.0min +/- to 20,000ft, and 443+/- top speeds. It also shows the "Standard" performace figures of 1,425hp @54in/hg (military power) and 414mph and a Normal power 1,100hp climb of 9+ min to 20,000ft. P-51 info is also included for comparison. I have seen this info elsewhere and will post it when I find it again in a format I can post.
The source of this information is in part Warren Bodie who is considered in aviation and aviation history circles a serious, respected, accurate and reliable source.
The Planes and pilots web page is at http://home.att.net/~C.C.Jordan/index.html
wmaxt
A
Anonymous
Guest
wmaxt said:
If these are government/military tests the information cannot be privately copyrighted, as it is by default property of the public. If they are lockheed tests, then the authors of the book again have no proprietary rights to them, they'd be lockheed property - thus the author's copyright would be meaningless. In order to copyright something you have to own the rights to it in the first place. Simply having exclusive access to something does not convey such rights.
A good example of this is the Aussie who found a trunk of unpublished Beatles material they recorded impromptu while in Austrailia at some beach house. He tried to copyright it but the law said no - it was property of the Beatles.
"half" internal fuel is contrary to US combat testing procedures, which dictate that the plane should have full internal fuel and that climb tests be conducted first after takeoff.
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Lunatic
A
Anonymous
Guest
The data seems to correspond to this chart:
from: http://home.att.net/~ww2aviation/P-38.html
found on this sub-page: http://home.att.net/~ww2aviation/P-38-3.html
along with some other interesting charts.
Since this is unverified company data with no references listed and it does not conform to other known test data, I'm a bit skeptical of its validity. If you can provide more context for the test - i.e. that it is at half fuel, that tends to legitimize it some - but the P-51 climb shown is at full fuel (minus 25 lbs out of the rear tank)!
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Lunatic
from: http://home.att.net/~ww2aviation/P-38.html
found on this sub-page: http://home.att.net/~ww2aviation/P-38-3.html
along with some other interesting charts.
Since this is unverified company data with no references listed and it does not conform to other known test data, I'm a bit skeptical of its validity. If you can provide more context for the test - i.e. that it is at half fuel, that tends to legitimize it some - but the P-51 climb shown is at full fuel (minus 25 lbs out of the rear tank)!
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Lunatic
FLYBOYJ
"THE GREAT GAZOO"
Great chart!
wmaxt
Staff Sergeant
I was of the understanding that it was half fuel used in Military Testing. 
These are supposed to be Military Standard Test conditions. The chart would be meaningless if they were configured differently. Also the normal power climb is a match for published climb data. The other charts also show figures as is seen published in other places like the 414mph @ 1,425hp. I feel the data there not only makes sense, jibes with published data but is accurate. These graphs also match many of the Pilot accounts of relative performance of the P-38 though the subjective nature of those accounts must be taken into account.
I will look for better confirmation for/against and post it when I find it. C.C. Jordan "Claims" to have AAF tests that confirm the data in these charts. They are supposed to be available as Paper records in the AAF archive. Where that is and how to access them well your guess is probably a lot better than mine. The sad part in that I worked near Wright Patterson AFB a few years ago and probably could have checked it out if I'd known (presuming the AAF archive is there).
The rest of the charts are in the third part of the P-38 article in Planes and Pilots of WWII. For anybody interested in the Air War over Europe should check it out. Their web address is shown above.
wmaxt
These are supposed to be Military Standard Test conditions. The chart would be meaningless if they were configured differently. Also the normal power climb is a match for published climb data. The other charts also show figures as is seen published in other places like the 414mph @ 1,425hp. I feel the data there not only makes sense, jibes with published data but is accurate. These graphs also match many of the Pilot accounts of relative performance of the P-38 though the subjective nature of those accounts must be taken into account.I will look for better confirmation for/against and post it when I find it. C.C. Jordan "Claims" to have AAF tests that confirm the data in these charts. They are supposed to be available as Paper records in the AAF archive. Where that is and how to access them well your guess is probably a lot better than mine. The sad part in that I worked near Wright Patterson AFB a few years ago and probably could have checked it out if I'd known (presuming the AAF archive is there).
The rest of the charts are in the third part of the P-38 article in Planes and Pilots of WWII. For anybody interested in the Air War over Europe should check it out. Their web address is shown above.
wmaxt
A
Anonymous
Guest
wmaxt said:I was of the understanding that it was half fuel used in Military Testing.
wmaxt
There were. And these were full fuel - climb test, speed test, altitude test - in that order. Sometimes the altitude test was done seperately for fuel availability reasons. Altitude was supposed to be measured under the definition service ceiling = 500 fpm climb at normal power, but this seems to have also typically been supplanted by the 100 fpm climb at MP figures, and sometimes even at WEP (for the few planes which could make WEP at extreme altitude) data which is almost always quoted.
Manufacturer tests however were not subject to these standards. Also, manufacture climb tests sometimes use the "wheels off" standard used by many other nations for time-to-climb - the US military standard was "brake off", which can make a huge difference.
The only thing that makes me suspicious about these figures is that I'm pretty sure they come from Lockheed, not the USAAF, and the figure for the (I'm pretty sure a late model) P-38J is 5.9 minutes to 20K @ 60" hg. The late model P-38J had the same engines as the P-38L but weighed less and carried less fuel. I don't think 4" more manifold pressure would make an almost 2 minute difference in climb. Clearly however, 1/2 fuel + 64" hg. (or more) manifold pressure + measure from "wheels off" could make that much difference. Also, doing the test from cold condtions could add a little to the climb (denser air makes for better airfoil lift and more engine power).
What I'd really like to see is the date and location of the test and the test conditions from Lockheed.
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Lunatic
FLYBOYJ
"THE GREAT GAZOO"
RG_Lunatic said:wmaxt said:I was of the understanding that it was half fuel used in Military Testing.
wmaxt
There were. And these were full fuel - climb test, speed test, altitude test - in that order. Sometimes the altitude test was done seperately for fuel availability reasons. Altitude was supposed to be measured under the definition service ceiling = 500 fpm climb at normal power, but this seems to have also typically been supplanted by the 100 fpm climb at MP figures, and sometimes even at WEP (for the few planes which could make WEP at extreme altitude) data which is almost always quoted.
Manufacturer tests however were not subject to these standards. Also, manufacture climb tests sometimes use the "wheels off" standard used by many other nations for time-to-climb - the US military standard was "brake off", which can make a huge difference.
The only thing that makes me suspicious about these figures is that I'm pretty sure they come from Lockheed, not the USAAF, and the figure for the (I'm pretty sure a late model) P-38J is 5.9 minutes to 20K @ 60" hg. The late model P-38J had the same engines as the P-38L but weighed less and carried less fuel. I don't think 4" more manifold pressure would make an almost 2 minute difference in climb. Clearly however, 1/2 fuel + 64" hg. (or more) manifold pressure + measure from "wheels off" could make that much difference. Also, doing the test from cold condtions could add a little to the climb (denser air makes for better airfoil lift and more engine power).
What I'd really like to see is the date and location of the test and the test conditions from Lockheed.
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Lunatic
I worked with flight test engineers at Lockheed, some of them were there in the early 40s and it seems that the engineers along with guys from design (Ole Kelly to name one) would set the profile for the flight test on "inhouse stuff." I could tell you that when I was there and these guys were getting ready to retire, much of the midset was the same in 1980 as it was in 45'.
wmaxt
Staff Sergeant
I can understand your reluctance to accept this data at face value but a couple of things to consider.
If Lockheed was selling me this aircraft with this data I'd think twice too. This data was researched and released through Bodie in the late '80s not by Lockheed to sell the plane.
The P-38J had V1710-17 /15 series engines of 1,600hp. The P-38L had V1710-30 series engines of 1725hp.
The P-38L in METO power is 1,425hp and 414mph, 1,725 in WEP to get to 443mph. A 29mph increase for 600hp.
The P-51D in METO is 1,495hp for 424mph and 1,650hp in WEP for 437mph. A 13mph change for 155hp.
That's 4 times the hp for the P-38 to have roughly twice the increase in speed. Which with the P-38 nearing it's criticle mach works with the "As speed doubles drag (and hp) increasses by four times" rule. Remember were only talking an increase of 6.5% in speed. I also say up front that more speed from the P-38 would need extensive redesign like the P-51 and P-47 got to get their speeds above 450mph.
If we can get better definition of the tests and they are lower I'll accept it but at least for now these are the best indication of the P-38 performance above METO throttle settings. So for now I'm going to stick with these numbers.
I will keep on looking and I will post the data I find regaurdless if it matches or is lower. I am sure you will too.
wmaxt
If Lockheed was selling me this aircraft with this data I'd think twice too. This data was researched and released through Bodie in the late '80s not by Lockheed to sell the plane.
The P-38J had V1710-17 /15 series engines of 1,600hp. The P-38L had V1710-30 series engines of 1725hp.
The P-38L in METO power is 1,425hp and 414mph, 1,725 in WEP to get to 443mph. A 29mph increase for 600hp.
The P-51D in METO is 1,495hp for 424mph and 1,650hp in WEP for 437mph. A 13mph change for 155hp.
That's 4 times the hp for the P-38 to have roughly twice the increase in speed. Which with the P-38 nearing it's criticle mach works with the "As speed doubles drag (and hp) increasses by four times" rule. Remember were only talking an increase of 6.5% in speed. I also say up front that more speed from the P-38 would need extensive redesign like the P-51 and P-47 got to get their speeds above 450mph.
If we can get better definition of the tests and they are lower I'll accept it but at least for now these are the best indication of the P-38 performance above METO throttle settings. So for now I'm going to stick with these numbers.
I will keep on looking and I will post the data I find regaurdless if it matches or is lower. I am sure you will too.
wmaxt
A
Anonymous
Guest
wmaxt said:
The info I have for the J series is that it had the Allison V-1710-89(91) engines, developing 1425 HP (normal power), vs the L series V-1710-F30R(F30L), also refered to as the -111/113 engines developing 1475 HP (normal power). The empty weight of the L was over 1300 lbs higher than the empty weight of the J.
The big problem I have with the Lockheed figures is that I suspect these derive from the "YIPPEE" plane, which was a P-38J, the 5000th unit off the line, and it had the engines off the L version so it was really sort of a light-weight L.
This plane was hopped up and used for both flight tests and stunt flying by Lockheed test pilots at airshows. I think it also had water-injection (which i don't think the production units had but I'm not sure of that). It was painted Red with the word "YIPPEE" painted across the bottom of the wing in big letters.
Edit: (here's a quote I found since writing this post)
While this plane showed the potential of the P-38, it is not representative of the planes combat performance levels. Lockheed would however have the data related to it and for company vanity reasons sneak it in as P-38J or L data. Lockheed is a very proud company after all (and with good reason).
So I'm suspicious of the Lockheed company test data as I think I've got good reason to believe it does not reflect a real combat plane's performance. For that matter, I'm somewhat suspicious of all company data unless it is confirmed by miltary testing at a later date and within reasonable margins of comparability.
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Lunatic
FLYBOYJ
"THE GREAT GAZOO"
RG - I would definitely agree with you!
the lancaster kicks ass
Major General
- 19,937
- Dec 20, 2003
yes i never believe predicted figures or figures of prototypes untill they haved pulled off them stats in combat.........
FLYBOYJ
"THE GREAT GAZOO"
Even during the war years as so true today, the manufacturer has one thing in mind - SELL AIRPLANES. Sure, they want to give you a quality product, but they are going to make that product look as good as possible, so they could MOVE UNITS and MAKE PROFITS. You should have seen what the Lockheed marketing pukes did and said during the L1011 days!
wmaxt
Staff Sergeant
FLYBOYJ said:
While I do agree with both you and RG at least to a point. There are at least two refrences that dissagree with your points. Again these graphs were not made public until the late '80 and not by Lockheed even then.
RG that engine data is for the Sub Series of the engines. the actuall series numbers for the L was like this V-1710-30-111/113 with the 111/113 denoting right or left rotation and other specific build details like intake manifolds. These engines are in those logs starting with P-38L-1-LO. My source for the engine data is the Lockheed build logs as published in Warren Bodies Book "The P-38 Lightning" as well as the "Planes and Pilots" web site. As you have noted and backed up the J engine (which was also used in the H model) was capable of 1,600hp, 125 extra hp out of an additional 4in/hg is not unreasonable with an engine of that size. Isn't the difference between 1,425hp @ 54in/hg to 1,600hp at 60in/hg simalar? Warren Bodie is respected for his accuracy not fabricationand has been since the 1950's.
Water injection is not referenced in the production aircraft.
There is NO reference anywhere that YIPPEE was "Hopped up". The plane Tony LeVier used in the ETO for exhibitions was available off the line there. There is no reason to belive the red plane was different. The aircraft Mattern used for the same purposes was also picked out of delivered aircraft supplies.
As you have noted before RG derated data was released while the aircraft were in service and that data continues to be used today. That does not make the data more correct.
Skepticism is good but we know that the usual specs for the P-38 are at METO power because they specify the power level. The WEP capabilities MUST be between the two numbers. The numbers used in the "Planes and Pilots" article may be high but there as/more accurate as a comparison of WEP figures of other aircraft to the P-38s METO figures so many people use. This data is not unreasonable considering were talking a 6.5% increase above 20,000ft. Lets at least get information that relates on a one on one basis!
wmaxt
FLYBOYJ
"THE GREAT GAZOO"
wmaxt said:
I believe you are quite correct. After Tony LeVeir retired he ran an aviation safety consulting company out of the old Burbank Facilities, my ex-wife worked close to his office. Back then I did some part-time freelance writing for a local aviation newspaper called Aerotech News and Review. I interviewed LeVeir on two occasions and remember him taking about "YIPPEE." It was stock and he, "Fish" Salmon and Milo Burcham all flew that aircraft around at one time or another. I remember him telling me that only thing special about "YIPPEE" was the paint.
wmaxt
Staff Sergeant
FLYBOYJ said:
Thanks! You may know more of the truth about the P-38 than any of us.
Belive it or not I want the correct data to use. I also agree that one set of data without back-up is suspect. I've looked at the data presented in these references from many angles as presented here and feel that it is not unreasonable as presented in the "Planes and Pilots" web page. Saying that does not mean it is all correct with out a doubt but it fits the empirical data from first hand accounts to the tests that are considered gospel.
Lets level the playing field?
wmaxt
A
Anonymous
Guest
FLYBOYJ said:
Several references I've read indicate the YIPEE had the engines from the L, not the J. However, this may have applied to all the very late J series planes, just before the switch over to L production? Also that it was carefully polished, the non flush rivets were filed flat, and it had no armor and faked guns.
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Lunatic
the lancaster kicks ass
Major General
- 19,937
- Dec 20, 2003
RG said:
which would have had a huge effect on top speed as was shown with that specail Bf-109 that i believe it was alder posted the stats for, and it's rediculous to believe stats from a plane with no armour, heavily polished and had fake guns, as being the same as data a combat ready plane could reach...........
